Which one is correct?

Options

A. In dorsiventral leaf, stomata are on lower (abaxial) surface
B. Protoxylem disintegrates to produce lacuna, (lysigenous) in monocot stem
C. Reticulate venation in dicot leaf, parallel venation in monocot leaf
D. All

Answer

To determine which statement is correct regarding the anatomy of flowering plants, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Analyze Option One**:
- The statement claims that in dorsi-ventral leaves, stomata are located on the lower (abaxial) surface.
- This is correct because dorsi-ventral leaves, typically found in dicots, have their stomata primarily on the lower surface to minimize water loss and to optimize gas exchange.

2. **Analyze Option Two**:
- The statement suggests that dorsi-ventral leaves disintegrate to produce lacunae or lysigenous cavities in monocot stems.
- This statement is also correct. In monocots, the disintegration of certain cells can lead to the formation of cavities, contributing to the structure of the stem.

3. **Analyze Option Three**:
- This option states that dicot leaves exhibit reticulate venation while monocot leaves show parallel venation.
- This statement is correct as well. Dicot leaves typically have a network-like pattern of veins (reticulate venation), while monocot leaves have veins that run parallel to each other.

4. **Analyze Option Four**:
- This option claims that all three previous statements are correct.
- Since we have established that Options One, Two, and Three are all correct, this statement is also correct.

### Conclusion:
All four options are correct. Therefore, the correct answer to the question is Option Four: "All because these three statements are correct."

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